News Corporation chairman and chief executive Rupert Murdoch has used his newly acquired technology conference D6 to throw his weight behind "rock star" Barack Obama's presidential campaign, as well as giving his views on the Wall Street Journal.

Murdoch made critical comments about the number of journalists involved in editing at the Wall Street Journal, which became part of the News Corp empire when he bought parent company Dow Jones in December, saying that every story seemed to be edited by "8.3 people".

Speaking at the Wall Street Journal D6 conference in Carlsbad, California, Murdoch was asked by veteran tech correspondent Walt Mossberg if he had played a part in the New York Post's endorsement of Obama.

"Yeah," he replied, candidly. The select audience of entrepreneurs and digital business executives at the conference earlier this week cheered, as can be seen in the accompanying video.

"We're on the verge of a complete phenomenon," Murdoch said. "Politicians are at an all-time low and are despised by 80% of the public, and then you've got a candidate trying to put himself out above it all. He's become a rock star. It's fantastic.

"There are a lot of problems. The education system in this country is a total disgrace."

Murdoch heaped praise on Obama, saying he was a "highly intelligent man with a great record at Harvard", but stopped short of a full personal endorsement because he wanted "to meet him personally".

"The Obama phenomenon and undoubtedly the recession and everyone getting hurt... the average American family today is really financially hurting and that all bodes well for him," he said.

"He may not carry Florida because the Jewish people are suspicious of him, and so are Hispanics. But he'll probably add Ohio and others. He will probably win."

Despite saying he was a friend of John McCain, Murdoch said the Republican presidential nominee had "a lot of problems".

"McCain has been in congress a long time and you've got to make too many compromise," he said.

"What does he really stand for? He's a patriot - he's a friend of mine and a really decent guy - but he's unpredictable.

"[He] doesn't know much about the economy and - I say this sympathetically - I think he has a lot of problems."

Murdoch said Hillary Clinton was in the race because her husband was pushing her to continue, but Obama would not want to make her number two in a new administration, because he would want to break with the past.

"There are things we do that can be changed and made better," he said.

"We'll have more reporters wherever we need them. But every story at the moment in the Journal is, on average, touched or edited by 8.3 people. I'm serious," Murdoch added.

"Everybody who goes to it says what about this or what about that - and people don't have time for that.

"There's not a story you can't get all the facts in in half the space. I'm not talking about your column Walt - relax."

Murdoch defended the decision to keep subscription access to the WSJ website, saying: "We have 2,000 great journalists, and if we can't fashion a valuable site, there is something wrong with us.

Asked if newspapers and magazines had a future in print, Murdoch said he was neutral but predicted a decline in editorial quality.

"I don't care if it's printed, on the web, on mobile or whatever. Look at the last six months - the average newspaper is down 10 to 30% in advertising revenue and those are problem margins. They have made every economy possible in production but not in journalism," he added.

"Now they have to turn to journalism and they are going to deteriorate tremendously."

Murdoch also confirmed that News Corp has held informal discussions with both sides during the aborted recent $47.5bn (£24bn) Microsoft takeover bid for Yahoo.

Looking relaxed and focused, Murdoch said Microsoft was right to be worried about the threat from Google and its "bright, ambitious people", and should get back around the negotiation table with Yahoo.

Microsoft, he said, needed to do whatever it took to get Yahoo back to the table, just as News Corp had when it started takeover talks with MySpace in 2005.

Viacom was "three days away from closing the deal," said Murdoch, who promptly offered MySpace's parent firm $50m more than the rival media giant to clinch the takeover.

The audience laughed when Murdoch insisted that Fox News, his US right-wing TV channel, was balanced.

"Fox gives both sides that the others haven't done in the past," he said.

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